He also served as President of the RAOU 1913-1914 as well as organising ornithological expeditions to the Bass Strait islands and to central and northern Australia.
He made his greatest impact as a photographer and conservationist when he reported his two visits to the St Helena swamp in the Emu (October 1907)'[1] In 1906 and 1907 Mattingley made two trips to the St Helena swampland on the Edward River to the northeast of Mathoura.
To increase support for the Bill and 'to bring home the truth of the matter to those whom words may not have convinced' the Royal Society for the Protection of Birds in Britain turned Mattingley's images into a mini-campaign 'The Story of the Egret'.
[4] Groups of uniformed sandwich board men paraded around London, bearing enlargements of the photos.
[5] The photographs contributed to the long-running campaign to eliminate the fashion industry's use of bird feathers.
A report in 2016-2017 noted that 'Large waterbird nesting events have been recorded within Millewa Forest since early in the 20th century (Mattingley, 1907, 1908).